Vent assembly for fuel tanks

ABSTRACT

A vent assembly for use on a tank containing liquid fluid requiring venting, the assembly comprising: a vent portion that includes a top surface, and at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the vent portion is disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the vent portion below the top surface of the vent portion.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. provisional patent application No. 60/741,132, filed Nov. 30, 2005, entitled CAP FOR FUEL TANKS, which is hereby incorporated by reference for all purposes as if included herein in its entirety.

BACKGROUND

The inventive subject matter relates to a vented cap and other vent assemblies primarily for tanks containing liquids that require venting. The inventive subject matter is particularly directed to venting fuel tanks used with motor vehicles. The fuel tank may be for holding gasoline, diesel, alcohol, and other liquid fuels for an internal combustion engine. In certain respects, the inventive subject matter relates to a vented fuel cap having a rollover valve, or check valve for use with fuel tanks on motor vehicles.

Fuel tanks for many motor vehicles include direct venting so a vacuum doe not form in the tank as fuel is withdrawn by an associated motor or engine. A problem with such fuel tanks is that if tank is tipped or turned over, the fuel in the fuel tank can leak out of the vent holes in the fuel cap potentially causing disastrous results. This is particularly problematic for off-road vehicles, such as motorcycles and all terrain vehicles, which are especially at risk of tipping or turn over.

Vented fuel caps are known that include an angle-dependent valve, such as a rollover or check valve device that operates to prevent fuel from leaking from the vents holes of the fuel cap when a fuel tank is tipped or turned over. For example, one known fuel cap includes a hose that extends outwardly from the center of the fuel cap that includes a rollover, or check, valve device at the end of the hose distal from the fuel cap. While a vented fuel cap of this type generally operates as designed, problems may still occur. For example, if the hose breaks, the check valve functionality may be lost. Also, for example, the hose and rollover-valve device can inflict a puncture-wound to a rider sitting in proximity to the tank.

Another known vented fuel cap includes a rollover-valve device located under the cap portion of the fuel cap and has a venting hole that emerges through the top side of the cap portion. There are problems with this arrangement too. For instance, the venting-hole arrangement can become clogged with dirt or other debris, eliminating the benefits of the venting hole.

In view of the foregoing and other problems, there is a need for improved caps for fuel tanks that have an angle-dependent valve, such as a rollover or check valve device that is not easily blocked or broken, and do not present a potential source of a puncture-wound injury.

SUMMARY

A vent assembly for use on a tank containing liquid fluid requiring venting, the assembly comprising: a vent portion that includes a top surface, and at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the vent portion is disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the vent portion below the top surface of the vent portion.

These and other embodiments are described in more detail in the following detailed descriptions and the figures.

The foregoing is not intended to be an exhaustive list of embodiments and features of the present inventive concept. Persons skilled in the art are capable of appreciating other embodiments and features from the following detailed description in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The inventive subject matter is illustrated by way of example and not by limitation in the accompanying figures in which like reference numerals indicate similar elements and in which:

FIG. 1 depicts a side cross-sectional view of an assembled fuel cap according to the inventive subject matter;

FIG. 2 depicts an side cross-sectional exploded view of a fuel cap according to the inventive subject matter; and

FIG. 3 depicts a top view of a slotted disc according to the inventive subject matter.

DETAILED DESCRIPTION

FIGS. 1 and 2 depict a vented fuel cap 100, according to one possible embodiment of the inventive subject matter. The cap has an angle-dependent valve, which as used herein means a valve or other flow restrictor that is provided in the cap to block fluid from flowing from a tank and out of a channel used for venting the tank, the flow being blocked upon a predetermined tilting of the cap from an initial position, which typically is an upright position on top of a fuel tank (as represented by the orientation of cap 100 in FIG. 1). A typical angle-dependent valve is a rollover valve or check valve, and the following discussion will be in terms of such a construction.

Fuel cap 100 includes a cap portion 101, a slotted disc 102, a valve assembly 103, a splash cover 104, and a gasket 125. Valve assembly 103 operates to prevent fuel from leaking through venting channels 107 in the fuel cap when a fuel tank on which the fuel cap is installed is tipped sufficiently or turned over. Motor vehicles that are particularly prone to tipping or turn over include motorcycles, ATVs, personal watercraft, and other recreational, transport or work vehicles that are prone to tipping or turnover, particularly those where the rider and/or fuel tank is unenclosed.

Cap portion 101 includes a top surface 101 a, a bottom surface 101 b, an inner surface 105, a vent chamber 106, vent channels 107 with exit openings, communicating with the atmosphere external to the tank 200, threads 108 and threaded blind holes 109. Inner surface 105 receives slotted disc 102 when fuel cap 100 is assembled. Vent channels 107 are in venting communication with a fuel tank via vent chamber 106 and extend away from top surface 101 a and emerge from bottom surface 101 b. While two vent channels are depicted, it should be understood that any number of vent channels 107 can be used. Additionally, while channels 107 are depicted as emerging from bottom surface 101 b, it should be understood that channels 107 can emerge from a surface that is below top surface 101 a. Threads 108 engage with corresponding threads of a fuel tank filler neck 200. Cap portion 101 is typically formed from any suitable material, such as aluminum, that is sufficiently strong and durable to function as a cap for a fuel cap assembly.

As shown in FIG. 3, slotted disc 102 includes a vent passage 110, venting aperture 111, and screw apertures 112. When slotted disc is received by inner surface 105 of cap portion 101, vent aperture 111 is in venting communication with vent chamber 106 through vent passage 110. While vent passage 110 is depicted as generally transversing slotted disc 102 in a bisecting configuration, it should be understood that vent passage 110 could have any of a number of configurations, such as at least one or more radially configured vent passages. Additionally, slotted disc 102 can be formed from any suitable material, such as aluminum, that has sufficient strength and durability to be held against cap portion 101.

Valve assembly 103 is a gravity-sensitive valve arrangement that blocks a passage based on a predetermined amount of tilting. In one possible example, a suitable valve arrangement is a check valve that includes a valve mount 113, a ball valve seat 114, a ball 115 and a return-air valve 116. Valve mount 113 is held against surface 117 of slotted disc 102 by screws 118 passing through apertures 119 in valve mount 113 and apertures 112 of slotted disc. Screws 118 are received in threaded blind holes 109 in cap portion 101. Ball valve seat 114 is received in cavity 120 of valve mount 113. Cavity 120 is then in venting communication with vent aperture 111 of slotted disc 102. Ball 115 is received in vent cavity 121 of ball valve seat 114. Vent cavity 121 is in venting communication with cavity 120. Ball 115 can be made from any suitable material that is denser and therefore heavier than the fuel that will be contained in the fuel tank on which fuel cap 100 will be used. Return-air valve 116 is also received in vent cavity 121 of ball valve seat 114, thereby retaining ball 115 within vent cavity 121. The components of valve assembly 103 can be formed from any suitable material, such as aluminum, that provides sufficient strength and durability to operate as a rollover (check) valve assembly.

Splash cover 104 includes a barb engagement slot 122 and vent channels 123. Barb engagement slot 122 engages barb 124 on valve mount 113, thereby fixedly holding splash cover 104 about valve assembly 103. Splash cover 104 can be formed from any suitable material, such as plastic, that provides sufficient strength and durability to be used as a splash cover for a vented fuel cap.

Gasket 125 fits into cap portion 101 and forms a seal with the filler neck of the fuel tank. Gasket 125 can be formed from any suitable gasket-type material, such as rubber.

In a typical operation, fuel cap 100 is installed in the filler neck of a fuel tank of a vehicle in a well-known manner so that fuel cap seals the fuel tank.

When the fuel tank and fuel cap 100 are in a normal, upright position, there is a vent passage through vent channels 123, return-air valve 116, vent cavity 121, cavity 120, vent aperture 111, vent passage 110, vent chamber 106 and channels 107. In the normal, upright position, ball 115 sits on return-air valve 116, thereby allowing normal venting to occur.

When the fuel tank and fuel cap 100 are in a sufficiently tilted or an inverted position, ball 115 closes vent cavity 121, thereby preventing fuel from spilling from fuel cap 100 through vent channels 123, return-air valve 116, vent cavity 121, cavity 120, vent aperture 111, vent passage 110, vent chamber 106 and channels 107.

While the inventive subject matter has been discussed in terms of a removable cap, a tank might be constructed with a fixed section incorporating an angle-dependent valve as contemplated herein. The tank could, for example, include a separate openable cap or other mechanism for adding or draining fluid from the tank, in addition to the fixed valve assembly. Accordingly, instead the inventive venting features of the cap may be instead implemented as a fixed “venting portion” on a tank.

Persons skilled in the art will recognize that many modifications and variations are possible in the details, materials, and arrangements of the parts and actions which have been described and illustrated in order to explain the nature of this inventive concept and that such modifications and variations do not depart from the spirit and scope of the teachings and claims contained therein. 

1. A vented cap for use on a tank containing liquid fluid requiring venting, the cap comprising: a cap portion that includes a top surface, and at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the cap may be engageably disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the cap below the top surface of the cap portion.
 2. The vented cap of claim 1, further comprising an angle-dependent valve assembly disposed in the cap and capable of fluid communication with the at least one venting channel and the tank.
 3. The vented cap of claim 2 wherein the cap is configured for use as a fuel cap for the fuel tank of a motor vehicle.
 4. The vented cap of claim 3 wherein the angle-dependent valve assembly comprises a rollover or check valve assembly disposed below the top surface of the cap portion.
 5. The vented cap of claim 4 wherein the cap is configured for use on a fuel tank for a motorcycle, all-terrain vehicle, or personal watercraft.
 6. An assembly comprising: a vented cap for use on a tank containing liquid fluid requiring venting, the cap comprising a cap portion that includes a top surface and at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the cap may be engageably disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the cap below the top surface of the cap portion; and a tank to which the cap may be engageably disposed.
 7. The assembly of claim 6 wherein the tank comprises a tank for a motor vehicle.
 8. The assembly of claim 7 wherein the motor vehicle is a motorcycle, all-terrain vehicle, or personal watercraft.
 9. The vented cap of claim 7, further comprising an angle-dependent valve assembly disposed in the cap and capable of fluid communication with the at least one venting channel and the tank.
 10. A method of making a vented cap, comprising: providing a cap portion for a removable cap for a tank requiring venting of a liquid that may be contained in the tank; providing in the cap portion at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the cap may be engageably disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the cap below the top surface of the cap portion.
 11. The method of claim 10, further comprising associating with the cap portion an angle-dependent valve assembly and capable of fluid communication with the at least one venting channel and the tank.
 12. The method of claim 11 further comprising configuring the cap for use as a fuel cap for the fuel tank of a motor vehicle.
 13. The method of claim 12 wherein the angle-dependent valve assembly comprises a rollover or check valve assembly disposed below the top surface of the cap portion.
 14. The method of claim 13 wherein the cap is configured for use on a fuel tank for a motorcycle, all-terrain vehicle, or personal watercraft.
 15. A vent assembly for use on a tank containing liquid fluid requiring venting, the assembly comprising: a vent portion that includes a top surface, and at least one venting channel, each venting channel capable of providing fluid communication between a tank on which the vent portion is disposed and atmosphere external the tank, the channel having an exit to atmosphere that is disposed on the vent portion below the top surface of the vent portion.
 16. The assembly of claim 15, further comprising an angle-dependent valve assembly disposed in the vent portion and capable of fluid communication with the at least one venting channel and the tank.
 17. The assembly of claim 16 wherein the vent portion is configured for use as a fuel cap for a tank for an internal combustion engine.
 18. The assembly of claim 17 wherein the angle-dependent valve assembly comprises a rollover or check valve assembly disposed below the top surface of the cap portion.
 19. The cap of claim 1 wherein the exit is disposed on a bottom surface of the cap portion.
 20. The cap of claim 19 further comprising an angle-dependent valve assembly disposed in the cap and capable of fluid communication with the at least one venting channel and the tank. 